A test method for determination of air flow resistance of exterior membranes and sheathings is described. The test specimen is placed between two chambers with different air pressures and the volumetric air flow rate through it at a steady state is determined. The relevant experimental quantities can presently be measured with precision better than 0.5% and with an accuracy of 2 to 3%, using commercial instruments. However, the instrumental precision does not mean much, due to the uncertainty introduced by material variability normally occurring in commercial products.
This report presents the results of air leakage tests on polyethylene membranes installed in a frame wall. The results would be useful in evaluating the methods commonly used for installing such a component.
Describes construction of timber-frame housing to high level of airtightness. A target level of 0.4 ach at 50 Pa was set. At this level, total air control provides an extremely high level of comfort by eliminating draughts and by supplying precise amounts of fresh air where required. An air and vapour barrier was installed within the house structure.
Outlines the fundamentals of insulation and airtightness, proper air quality, and ventilation. Presents details of design and construction for walls, roofs, foundations, windows, and air-vapour barriers, as well as discussions of ventilation systems, heating systems, appliances and methods of testing and evaluation. One of the appendices gives weather data for selected US and Canadian cities. Aims to be accessible to the interested layperson or homeowner.
This report addresses the factors causing water vapour problems and provides insights into the solutions available with particular emphasis on vapour barrier paints. Concludes that 1. moisture flow in structures is a dynamic, systemic process of multiple variables, and therefore requires an integrated approach for management, 2. retrofit applications offer an entirely different set of physical and economic considerations than are found in new construction and therefore require a different approach, 3.
A database on the airtightness performance of houses built according to current construction practices (1980 to 82) was established, province by province, across Canada. Airtightness tests were conducted using the fan-depressurisation method and the results were compared by province, builder, house style, and house size. The survey shows considerable variation in the leakiness of the houses when the results are compared by province. Less variation in airtightness exists when the houses are compared by builder, house style, and house size on a provincial basis.
A spunbonded polyolefin air infiltration barrier (AIB) was installed immediately beneath the siding of a 5 year old ranch-style house. The AIB reduced the heating energy consumption by 27% during the first heating season and is expected to reduce the heating load by 28% over the remaining life of the house.
Discusses the Swedish trend to build super insulated nearly airtight dwellings. Mentions problems encountered in tight buildings, such as severe ground floor condensation and mould growth. Shows the importance of the vapour barrier in preventing condensation. Compares exhaust and balanced ventilation systems in tight houses. States that sealing houses in Sweden is costeffective, partly because of an integrated approach to incorporating energy saving features in new housing.
Fan pressurization tests on 2 unoccupied houses have been conducted once every 2 weeks for a period of a year to determine the seasonal variation in air tightness. House no.1 was built with more insulation than is required by the local building
Studies moisture conditions in homes in 2 studies. In one study, 17 homes in 4 states were probed in mid-March 1977, and all moisture content levels were found to be within the acceptable range of equilibrium moisture contents. Inanother study, collects data for 16 homes in north-central Utah, Southern Alabama, Northern Ohio and central Maryland. Makes measurements in each home for approx 1 week in the summer and 1 week in the winter. All homes have well-ventilated attics.